Drier



Oct. 11, 1938. H. l.; SCHMIDT DRIER Filed March 27, 19257 lllttlnt. H

Patented Oct.' l1, 1938 l UNifTiaii)v .STATES nsriow L. schmidt,Milwaukee, wis., mignonto The Heil Co., a corporation of Wisconsinapplication Maren 27,

c 4 Claims.

My present invention relates in general'to improvements in the art ofheating, and relates4 'more specifically to improvements in theconstruction and operation of internally heated drums having peripheralannular supporting ele- 5 ments or tires coacting with rotary memberssuch as rollers to rotatably support the drums.

Generally defined, an object-of the present invention is to provide animproved mounting. for rotary cylinders or the like, `and improvedinstrumentalities for preventing excessive heating of the supporting'elements.

It has heretofore been common commercial practice to support the drumsvof rotary driers, l kilns and the like upon tires secured to the outer i3 shells and coacting with rollers journaled in stationary supportingstructure. Due'to the intense internal heat, the supporting tires arefrequently subjected to sufficiently high temperatures to warp andotherwise distort the same, thereby not only producing irregularlrotation of the drums but also subjecting Vthe tires to excessivestress and possible rupture. It is however desirable for structuralreasons, to attach the tires directly to the shell of the drum near theend heads, and

.in extremely long-shells intermediate' tires may also be required.A Inmost devices of this general class, it is also undesirable to providedeep pockets near the end heads, withinwl'iich material tends toaccumulate, but dishing'of the heads in vorder to eliminate such pocketsis rather costly and objectionable for this reason.

My present invention therefore contemplates the provision of improvedmeans for preventing excessive heating of the supporting tires oi adrier drum or the like, due to internal heat.

My invention also contemplatesthe provision of improved means lforeliminating undesirably deep pockets near-the end heads of a drum,within which material tends to lodge. l,

' The Iinvention furthermore contemplates the provision of simple andeiective structure for insulating or-segregating the supporting tiresvoil! a drier drum 'fromthe internal heated zones by ventilated airspaces, while at the same time obviating deep materialcollectingcorners; and

` pockets within the shell of the drum.

` These and other specic objects and advantages of the present inventionwill be apparent from the following detailed description.

A clear conception of embodiments ofthe features constituting my presentimprovement, and of the mode of constructing "and of operating driersbuilt in accordance with this invent/ion, s maybe had by referring tothedrawing accompanying and forming a part of this specication fan Il isadapted to constantly create a now of 1937, seria. No. 133,365V

roi. 3.4-5)

wherein like reference characters designate the same or similar parts inthe several views.

Fig. 1 is a substantially longitudinal vertical section through a rotarydrierv embodying the improvement;-

Fig. 2 is a part sectional end view of the drier 5` of Fig. 1,lookingtowardthe feed end thereof Fig. 3 is a considerably enlargedsection taken through the feed en d corner of the drier drum of Fig. 1;and

' Fig. 4 is a similarly enlarged seetion'through 10 the feed end cornerof a slightly modiijled asf semblage. y

While my invention has been shown and described herein as beingspecifically applied to a particular type of drier drum and for thespecic 15 purpose of protecting a smooth annular periph.-

. leral tire from detrimental effects of internal heat,

it is not the .intent to thereby unnecessarily re;v strict the scope,since the improvement is also applicable to other types of rotary drumdrives 20 and for the protection of such drives against any ki'nri oftemperature changes. ,c

Referring to the drawing,- the improved drier shownratherdiagrammatically in Figs. 1 and 2, comprises in general a drumassemblage` consist- 25 ing of three concentric elongated shells 8, "I,8 and end closure heads 9, I0, II coacting therel with; a hot gas supplyduct or pipe I2 and a material supply spout I3 communicatingwlth thefeed end ofthe inner shell. 8; an outlet pipe Il 30 communicating withvthe' dischargel end of the outer shell 8 and with ari exhaust fan I5;peripheral tires I8 secured' to the opposite ends of the outer shell)adjacent to the end heads 9, III; and rota-ry supporting rollers I1coacting with the 35 tires I 6 and b'eing journaled in the bearings I8ki'carriedby suitable foundation beams I9. The gas supply pipe I2 is fixedand communicates with anysuitable source of hot'gas, and the materialsupply spout *I3 is also stationary and may be 40 provided with a rotoras Ashown for regulating the delivery of fibrous. or granular'materialinto the innerdrum shell 8 vwith the heated' gases. The outlet pipe I4is also stationary, and the exhaust 45 mixed gas and fibrous materialthrough the re-r volving drum assemblage and tov deliver the treatedmixture toa suitable separator. The interiors of the shells 0, 1. 8 mayalso be provided with 50 internal, nights for showering the solidparticles across the interiors of these shellsgso as -to en- .hance thedrying action, but these ilightsform no part of the present in ventio'nand have there- Iorebeen omitted in order to avoid confusion.

CTL

, The sheus s, 1, s and the end heads '91, lo,

may bevformed of sheet metal and are preferably closes an end of theshell 1.- The opposite end f the intermediate shell 1 is supportedconcentrically of the outer shell 8 by means of a similar ring 23 andgussets 24, near the end head 9;

and the space between the end heads I0, I I yhas a series of radialights 25 therein which cooperate with a cone 26 on the exterior of theend head Il to deliver the treated material into'the outlet pipe I4. Theouter end head I0 may alsobe pro-- vided with a sealing plate 20coacting with the l pipe I4, anda deflecting vcone 21 may also beprovided onthe inner face of the end head Il, but these details ofconstruction are relatively unimportant so. far as my present inventionis concerned. Itis to be noted, however, that the relative mounting ofthe concentric shells 6, 1, 8

:and the location of the end heads 9,- I0, II, is .A such thatacontinuous circuit'ous path is pro-v vided in the drum assemblage,extending from the inlet pipe I2 to the outlet pipe I4, and the gussets22, 24 as well as the flights 25 are radially disposed.

The tires I6 vare rigidly attached, as by welding, to the periphery ofthe outer shell 8, adjacent to the end heads 9, I 0,'and the gusset 24and -ilights'25 extend into theannular corners formed by the end headsandthe shell 8 directly within these tires. The shelli3 is also embracedby a jacket 28 of insulating material, which-extends 40 @from one tireI6 to the other, and the end heads 9, I0 may also be covered withr likelinsulation, if so desired. In accordance with the present invention,inorder to segregate the tires I6 from the heated interior`of the drum,a series of segment plates 29 are inserted across the corners of theouter shell' 8 between the successive radial gussets 24 and flights 25,`to ,provide substantially annular air'spaces 30 having substantiallytrivangular cross-section, as clearly shown in Fig. 3.

lIn order to vent`these annular spaces '36, the end heads 9, I0 areprovided with' openings 3l whereby the heated air may escape and coolair may ,enter the spaces 36. Besides providing insulating air spaces36, these segment plates v29 also eliminate the deeppockets exposed tothe Vdrum interior, and within which solid particles might other- I wisetend to accumulate, and these 'pockets are obviously done away'withwithout necessityyof Adisliing the end heads 9, I0.

The segment plates 29 may be eitherstraight or curved as shown, and thespaces 30 may be ad ditionally vented as in Fig. ,4, by shortening'the yinsulating jacket 28 andfby providing other openings 32 in the shell 6laterally adjacent 'tothe tires I6. Theradial gussets 24 and flights'25ex- .tending into the spaces 30, will'then act as fan blades 'tending todraw freshl air into the side' .openings 3I vand to deliver-.the Iperipheral openings 32.

During normal operation ofthe improved drier, heated gas from Aanysuitable source is being constantly delivered into the inlet end of thecentral shell s throughqthe pipelz, together with the material which isto be treated, this material being constantly discharged inregulated'quant1-- air through the shell providedwith end heads and an innershell ties from the supply spout I3 into the entering stream of hot gas.The drier drum is being constantly rotated from any suitable source ofpower, throughthe supporting rollers I1 which frictionally engage thetires I6. The suction fan I5 is operating to' constantly draw themixture of material and ,gases through the shells 6, 'I, B in successionas indicated by the arrows inrFig. 1,` and the ilights 25 normallyfunction to deliver the nally treated material' into the discharge pipeI 4 from whence it is withdrawn by the fan I5 and is delivered to theseparator. material admitted from the feed spout I 3 is constantly driedand is delivered in dried condition to a separator or other point ofutilization.

Because of the relatively high temperature of the gases passing throughthe drum, the shell 8 and end heads 9, I6 will naturally become heated.In order to prevent the tires I6 from becoming excessively heated, Ihave provided the segment plates 29 which form the chambers or spaces 30segregating the tires I6, from the heated interior of the drum. Whilethe air within the spaces 30 disperse -=this heat and will therebyprevent excessive heating of the tires I6. The plates 29, besidesproviding substantially annular insulating air spaces for the tires I6,also eliminate deep pockets between the successive radial v nes orplates at the corners formed by the junctions of the end heads 9 withthe shell 6, thereby preventing the material beingtreated fromaccumulating at these corners. The\provision of the openings 3I does notmaterially weaken the end heads 9, I 0, and if additional ventilation.of the spaces 30 is required, openings 32 such as shown in Fig. 4, mayalso be provided.

From the foregoing detailed description, it will be apparent. that thepresent invention provides simple and highly eflicient means forprotecting the tires I6 against excessive heating due to the vhighinternal temperatures prevailing within the drum. The tire insulatingmeans also functions to'prevent accumulation-of material in the cornersof the drum structure, and all of these advantageous resultsy areobtained by merely placing the segment plates 29 diagonally across thecorners and by`providing .ventilatingopenings 3|. ,The assemblage canobviously be produced at extremely moderate cost and vfunctionsautomatically to produce the desired results. l

It should be understood that it is not desired to limit thisinvention tothe exact details of In this manner, the

may tend to heat, the openings 3| will quickly construction or to theprecise mode of operation herein shown and described, for variousmodications within the scope of the claims may occurj to persons skilled inthe art.

` 1. In combination, an internally heated drum .having outer and innershells, an annular series 'of radial plates for .supporting said innershell from said outer shell, a tire secured to the periphery of saidouter shell-adjacent to said plates, anda series of segment platesvconnecting the successive 'supporting plates and providing an air spacebetween saidtire and the heated drum interior. "i

2. In combination,a drum having an outerl lwith said outer shell, a tiresecured to each end oi' said outer shell near the adjacent end head,

and a series ofsegment plates connecting the aisaova successiveradialplates near each endhead to p rovide air spaes between said tires .andthe interior of saidv drum.

3. In combination, a rotars1 drum having an annular end corner separatedinto segments by a series of plates, an annular driving element securedto said drum at said corner, and an annular series of segment plates,connecting said rst mentioned plates to provide an a'nnular air chamberat said comer separating said element frorn thedrum interior. Y

'42 1x1-combination, .a cy11ndricu drum having at each end an annularcorner divided into segments by a series of radialA plates, -an annular-tire'secured tothe periphery of said? drum at each` of the corneredends' thereof, and annular HARLQW L. scm/nur.

